Exterior oak door: Minwax Helmsman or Clear Shield?

CassandraMay 23, 2005

I'm staining and sealing a new unfinished oak exterior door. It is south facing in a brutal climate (Minnesota) although it will be protected by a good screen door. I received advice on this forum to use a UV protected marine spar urethane and I was going to buy the Minwax Helmsman. I just noticed, however, that Minwax also has what looks to be an even more durable exterior-type protective coat called Clear Shield. Clear Shield, it says, "is a great choice for wood finishing projects that need a clear finish that stands up to nature's elements." Any advice on which finish would be best?

Clear Shield does say it has UV protectors. What I can't figure out is how it actually differs from Helmsman. The (untrained) clerk at Menards said "it is the same thing only stronger." HandyMac, what exactly is a "clear finish" (versus a varnish or poly?)

For the longest lasting protection, use an exterior oil based trim and siding paint without color mixed in. This is generally referred to as a neutral base #4 (#5 with Olympic). The oil based products dry clear and will amber like spar varnish does. They last a lot longer than varnishes due to the addition of mildew and fungi killers and UV inhibitors.

In the link jrdwyer provided is a really good article on the tint base idea. I had never heard of using a tint base---but---paint is a better protectant than clear or opaque finishes. The tint bases recommended are simply clear paint. I've learned something here too!

Besides, the article was posted by Howard Acheson, who is very knowledgeable about finishing. I know Howie from another forum where he is one of the 'finishing guru's'.

This is a very interesting topic. I'm new to woodworking, drawn here as my new wood door is being installed and learning from my GC that a nonpainted door will not hold up for long if it gets any sun exposure. Who knew? Guess this isn't something I've paid any attention to in the past, but am learning way too much as we build our house. Anyway, I figured I could learn alot from you guys over here in WW and I sure did! Thanks for the info.

My GC went to the paint store yesterday, with the above linked article in hand (which I printed and gave to him), and I'm sure you'll be surprised to know received some resistance but willingness on the part of the clerk and a few customer painters in the store to do the paint stick experiment. He let them all read the article too, I guess while the stick dried. Success ~ it worked and caused quite a bit of painter excitement for our little town. My GC left the store with #4 in hand to experiment with at home. I'm half expecting to be interviewed by our local paper if this gets out. :o)

Thanks for your replies and the interesting information about the clear paint finish idea. I also decided to try it! Went down to my local paint store (they also sell lots of woodworking stuff) and also met with considerable skepticism on the part of the clerk. I insisted, he gave me the "well I'll just humor the little lady" look, and I left $26.00 dollars poorer with a quart of Benjamin Moore exterior oil tint base #4. It looks anything but clear in the can--a murky greenish gunk. I tried it on a sample piece of oak, stained with a Minwax stain. To my surprise it went on clear--no waiting for it to dry to become clear. I'm testing it next to a sample coated with Helmsman. We'll see how the samples look after sitting out in the hot sun for a few weeks, but right now they look exactly the same.

I tried two samples of oil paint deep base. Benj Moore left a green cast on fairly light colored wood and Porters deep base was tan. I think that either may work with thin coats on a dark wood. Both took more than a day to dry. That will be a real problem on a front door. I guess we will cover it with plastic and leave it part open. If you close it too soon you'll have to start over. When the weather warms, I plan to strip the door, stain and do the Porters.

I am amazed by this advice. Unfortunately the article links are now dead ends. I've had a fiberglass faced front door, southern exposure/no storm door, that I've had to varnish about every six months using Minwax's Clearshield varnish. It chips away in spots over time, although the last treatment done in October 2010 seems to be holding up well.

Could I switch over to oil based trim paint now, as suggested above, without removing the multiple coats of varnish?

It has been a few years since this first appeared and I wish I would have seen it sooner. I have a wooden front door, west facing and over the years the varnish dried up and thus so did the wood. I finally got tired of revarnishing so decided to paint it. After painting it red and then glossy black we just recently painted our house a dark color so wanted to strip and restain the door a red mahogany to complement the dark green house. I found an article that talked about using neutral base paint to protect the door and was so excited to try it. I went to the paint store, encountered the same wary sales clerks but they tested and saw that the paint dried clear and were then eager to hear how it works. I bought an acrylic exterior semi-gloss because I didn't want to leave the door off the front long enough for oil paint to dry. It looks wonderful! I have put two coats on so far, intend to add a couple more. I thinned it with water so it would go on smooth and dry quickly. So anxious to see how it lasts as I will try it on our back deck railings and some outdoor wood furniture that we built.

Over time the original text has gone stale, error, etc., so I'll copy and paste it here:

In a recent post my friend, Steve, made reference to my tests of doggie sprinkling on exterior finishes. I figure after almost a year of testing it is time to post some interesting discoveries. As a preface, allow me to set the stage. Almost daily there is a posting about clear, exterior finishes for doors, chairs, signs and such. Responses run the gamut from diehard marine finishes to apply a coat of primer and then paint. Each of these has a bit of a problem. Marine finishes are not always the easiest to find, and it grieves me to think of a lovely oak, teak, mahogany, fir, redwood or similar nice wood door painted in mauve goop.

Bob (from Florida) inspired me with his continuing and accurate statements about the failings of a clear coat and the advantages of a good quality exterior paint. I decided after lots of reflection that he really was right but there was always the picture of mauve in my mind. So, how could one take advantage of his advice and yet capitalize on the beauty of a nice wood? I began to reflect on the characteristics of paint. Now comes the boredom...

There were several things I knew about paint:

Exterior paints contain a mildewcide and a fungicide that a (marine) varnish does not.
The best quality paints will contain a UV (inhibitor) and trans-oxide pigments in very high percentages.
Almost all paint is custom mixed by the store. The retailer maintains a large supply of base products that are used to achieve the desired color.

There are generally four base products and the specific one for your paint is determined by your color choice. These base products are either named or numbered. They are named pastel, deep, tint and neutral. If numbered it is cleverly 1, 2, 3 and 4 with the exception of Olympic who numbers 1, 2, 3 and 5. Olympic is unaware that "4" comes before "5". Pastel and/or 1 is virtually a pure white and used for the lightest of colors. The others are slightly color altered from white and more translucent than pastel. These are used for succeeding deeper colors. All of this comes to neutral, 4 and/or 5. These are clear and used for (mixing) the darkest colors. In the can they are somewhat opaque but dry more or less clear.

Now comes the testing. I bought 4 oak exterior doors. Each door was given one coat of the same MinWax Stain. On 3 of the doors, I applied 2 coats of "base" to the 6 sides of each door (3 coats on the top and bottom edges). Each of these three doors had a different type of exterior neutral, 4 or 5 base. The fourth door was finished with a consumer "spar" varnish from my local friendly paint/hardware store. The bases for the 3 painted doors were an exterior semi-gloss acrylic, an exterior semi-gloss oil-based polyurethane floor paint, and a semi-gloss oil-based trim and siding paint.

The doors were set up, slightly inclined, in mostly direct sunlight under a pecan tree in the backyard. (My wife just loved that one.) Daily, the sprinklers managed to hit the doors. The birds in the pecan tree used the doors for target practice. And, yes, the dogs did anoint the doors on a regular basis. My blonde Cocker, Zazu, was particularly enamored with the doors. Over the course of the test the doors experienced lots of Texas sunlight, rain and snow. The temperature went from below freezing to over 100. The advantage to the inclined position of the doors was the snow, ice, water from the sprinklers and the rain tended to collect in the raised panel areas. I feel these doors were subjected to far more severe environmental conditions than would be expected from normal use.

The results were interesting. The "spar" varnish (initially) looked fabulous; but, after about 2 weeks it began to develop small cracks. In rapid order the door began to turn black, started to mold and the smell was enough to knock a buzzard off of a manure wagon. The water-based acrylic is milky in the can like a water-based poly. It dried to a more or less water clear surface but was a bit cloudy. It tended to wash out the stain a bit. Over time it became cloudier and ultimately become almost white. But, it remained solid and protected the wood. The oil-based bases are also a bit opaque in the can but dried to a clear finish that is almost identical to a spar varnish - they added an amber tone to the doors. Both the oil-based poly floor paint and the oil-based trim and siding paint remained "clear" over the entire test period.

The testing came to an end with a bit of encouragement. My wife said something clever like,"Get those damned doors out of the backyard!" She does not understand science. The floor poly had some minor checking and a thinned coat of the same base over the surface made that disappear. The door with the oil-based trim and siding paint was perfect, other than it had lost a bit of the gloss.

So, I am with Bob - paint the door. My preference is the oil-based products. If you are predisposed to a water-based use an acrylic rather than latex.

One thing you will find when you go out shopping for your product is a lack of knowledge on the part of the salesperson. Not many of these folk are aware that their neutral or 4 base will dry clear. If you want to have some fun, spring it on them. They will suggest you are full of Donkey Dust. Ask them to shake a can and put some on a stir stick. Dry it and voila, it is clear.

Jim

One final admonition; if you decide to try the paint solution you must understand that you are applying it like varnish, not like paint. Use a good natural fiber brush, keep your coats thin, (emphasis added; keep the coats thin! We recommend thinning with paint thinner to improve flow-out and leveling.) and brush the paint-base out into a thin, uniform film. If you apply the paint-base too heavily you will get a cloudy finish.